Streams from Apache 2.0 won't play until completely download

[stealthdave]

I've got a PHP script that streams video from my TiVo out to VLC, recompressing it on-the-fly to ASF format. Things work great when streamed from IIS, Abyss Web Server, and even Apache 1.3.x, but when I attempt to stream from Apache 2.0.x, VLC attempts to cache the entire stream before it will start to play. I captured the message window output from VLC for OS X in the cases of Apache 1.3.x and 2.0.x:

http://www.wiskars.com/tystreamer/header-apache1_3.txt
http://www.wiskars.com/tystreamer/header-apache2_0.txt

The project itself, TyStreamer, can be found here with all the source code used to stream the video. It only seems to be an issue if I use PHP (or possibly other CGI, such as Perl) to stream the video; if I try to load a file directly from Apache 2.0 (ala http://server:8080/file.asf), it works just fine. It's very puzzling that this problem is only occurring with Apache 2.0, especially since it works with Apache 1.3.

For more information, you can find a discussion thread on TyStreamer at Deal Database.

Any insight into what might be the problem would be greatly appreciated.

- Stealth Dave